EP2160922A1 - Système anti-larsen en ligne pour une prothèse auditive - Google Patents

Système anti-larsen en ligne pour une prothèse auditive

Info

Publication number
EP2160922A1
EP2160922A1 EP08760480A EP08760480A EP2160922A1 EP 2160922 A1 EP2160922 A1 EP 2160922A1 EP 08760480 A EP08760480 A EP 08760480A EP 08760480 A EP08760480 A EP 08760480A EP 2160922 A1 EP2160922 A1 EP 2160922A1
Authority
EP
European Patent Office
Prior art keywords
gain
feedback
maximum
predefined
frequency
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP08760480A
Other languages
German (de)
English (en)
Other versions
EP2160922B1 (fr
Inventor
Jesper Bünsow Boldt
Thomas Bo Elmedyb
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Oticon AS
Original Assignee
Oticon AS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Oticon AS filed Critical Oticon AS
Priority to DK12162551.1T priority Critical patent/DK2533551T3/en
Priority to EP12162551.1A priority patent/EP2533551B1/fr
Priority to EP08760480.7A priority patent/EP2160922B1/fr
Publication of EP2160922A1 publication Critical patent/EP2160922A1/fr
Application granted granted Critical
Publication of EP2160922B1 publication Critical patent/EP2160922B1/fr
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R25/00—Deaf-aid sets, i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception
    • H04R25/45—Prevention of acoustic reaction, i.e. acoustic oscillatory feedback
    • H04R25/453—Prevention of acoustic reaction, i.e. acoustic oscillatory feedback electronically
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R2430/00—Signal processing covered by H04R, not provided for in its groups
    • H04R2430/03—Synergistic effects of band splitting and sub-band processing
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R25/00—Deaf-aid sets, i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception
    • H04R25/50—Customised settings for obtaining desired overall acoustical characteristics
    • H04R25/505—Customised settings for obtaining desired overall acoustical characteristics using digital signal processing
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R25/00—Deaf-aid sets, i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception
    • H04R25/55—Deaf-aid sets, i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception using an external connection, either wireless or wired
    • H04R25/552—Binaural
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R25/00—Deaf-aid sets, i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception
    • H04R25/55—Deaf-aid sets, i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception using an external connection, either wireless or wired
    • H04R25/554—Deaf-aid sets, i.e. electro-acoustic or electro-mechanical hearing aids; Electric tinnitus maskers providing an auditory perception using an external connection, either wireless or wired using a wireless connection, e.g. between microphone and amplifier or using Tcoils
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/49005—Acoustic transducer

Definitions

  • the invention relates to feedback compensation in a hearing aid system comprising a feedback path with an adaptive filter for estimating acoustical feedback from an output transducer to an input transducer of the hearing aid system.
  • the invention furthermore relates to a method of adapting a hearing aid system to varying acoustical input signals, and to a method of manufacturing a hearing aid system.
  • the invention may e.g. be useful in digital hearing aids for use in a variety of acoustical environments.
  • the (open) loop gain is a product of the gain in the hearing aid and the coupling between the receiver (speaker) and microphone, primarily, but not exclusively, through a vent in the earpiece.
  • the vent is generally inserted in the earpiece of hearing aids so as to avoid occlusion.
  • the coupling between the receiver and microphone is called the external or physical or acoustical feedback path and may have other origins than a deliberately arranged vent, e.g. mechanical coupling between various parts of the earpiece, etc.
  • Two methods can be used to help in situations where loop gain gets too high: Either by subtracting an estimate of the external feedback from the input signal (the microphone signal) or by reducing the gain in the hearing aid.
  • the first method is used in so-called Dynamic Feedback Cancellation
  • DFC Direct Current
  • AFB Anti-Feedback
  • This method has the advantage that the loop gain can exceed 1 without howls, meaning that the hearing impaired can get more gain or a larger vent compared to a situation without a DFC/AFB-system.
  • a schematic illustration of a hearing aid system comprising a forward path, an acoustic feedback path and an electric feedback cancellation path is shown in FIG. 1b.
  • the second method is sometimes used in the fitting situation, where the external feedback is measured and the maximum allowable gain is adjusted ('the feedback manager', FBM). But this is typically a one-time (offline) measurement, possibly performed by a technician, such as an audiologist, typically using specially adapted equipment.
  • US patent no. 5,619,580 describes a hearing aid with digital, electronic compensation for acoustic feedback comprising a digital compensation circuit, including an adjustable digital filter and a first part, which monitors the loop gain and regulates the hearing aid amplification, so that the loop gain is less man a constant K, and a second part, which carries out a statistical evaluation of the filter coefficients, and changes the feedback function in accordance with this evaluation.
  • US patent no. 6,219,427 deals with a digital hearing aid comprising a feedback cancellation system in the form of a cascade of two adaptive filters, a first filter for modelling near constant factors in the physical feedback path, and a second, quickly varying, filter for modelling variable factors in the feedback path, the first filter varying substantially slower than the second filter.
  • WO 2006/063624 describes a hearing aid comprising a processor for amplifying an electrical input signal, an adaptive feedback suppression filter and a feedback model gain estimator that determines an upper processor gain limit based on inputs from the microphone, the adaptive filter, and the output form the processor.
  • EP 1 191 814 A1 deals with a hearing aid with an adaptive filter for suppression of acoustic feedback and a controller that is adapted to compensate for acoustic feedback by determination of a first parameter of an acoustic feedback loop of the hearing aid and adjustment of a second parameter of the hearing aid in response to the first parameter whereby generation of undesired sounds is substantially avoided.
  • An object of the present invention is to provide an alternative acoustic feedback compensation scheme, in particular, it is an object of the present invention to provide a system and a method for adapting the feedback compensation scheme of a hearing aid to changing conditions of a wearer of the hearing aid and/or the acoustical environment over time (typically over time scales of the order of seconds, minutes, days or months).
  • the general idea disclosed herewith relates to an online anti-feedback system, which continuously avoids or suppresses howls, by estimating the feedback path and adjusting the maximum allowable gain in the hearing aid.
  • the online anti-feedback system of the present invention uses the feedback path estimate to adjust maximum gain in the forward path (termed 'insertion gain' in the following). Thereby the resulting loop gain can be controlled, in an embodiment, the adjustment of the maximum allowable gain in the forward path is based solely on the feedback estimate (and predefined maximum loop gain values, without considering current loop gain).
  • the system is adapted to perform the adjustment of the maximum allowable gain in the forward path slowly compared to a normal, instantaneous feedback compensation system, e.g. with an update frequency smaller than 0.5 Hz or smaller than 0.1 Hz or smaller than 0.05 Hz or smaller than 0.01 Hz or smaller than 0.001 Hz.
  • the frequency range ⁇ f [ f min ; f max ] considered by the hearing aid system, e.g. limited to a part of the typical human audible frequency range, e.g.
  • FB frequency bands
  • FB 1 , FB 2 , .... , FB N frequency bands
  • LG(FB i ) IG(FB i )+FBG(FB i )
  • values of current loop gain, LG(t n ), and current feedback gain, FBG(t n ), used are typically maximum values of the parameter in question at the given time frame t n and frequency band i (termed LG max,i (t n ) and FBG max,i (t n ), respectively).
  • predefined (pd) maximum acceptable values for a given frequency band i of loop gain, LG max,i (pd), to avoid feedback oscillation are determined and stored in the hearing aid (e.g. set to different values from frequency band to frequency band or set to a constant value, e.g. -2 dB, in all frequency bands). Additionally or alternatively, predefined maximum acceptable values for a given frequency band i of insertion gain IG max,i (pd) can be determined and stored in the hearing aid.
  • the IG max,i (pd)- values are e.g.
  • the graph IG max-std indicates a standard setting of the predefined maximum acceptable forward gain for the different frequency bands, such as e.g.
  • IG max-FBM indicates a setting of predefined values (pd) of maximum acceptable forward gain, such as e.g. adapted by a hearing aid specialist, e.g. an audlologist, e.g. manually or using an offline 'feedback manager' (or using an automated procedure, e.g. a software tool running on a PC) to adjust the settings to a hearing profile of a given user (typically overriding the standard values IG max-std from the manufacturer).
  • a hearing aid specialist e.g. an audlologist
  • an offline 'feedback manager' or using an automated procedure, e.g. a software tool running on a PC
  • the graphs IG max-OFBM (t n ) schematically indicate values of the maximum acceptable forward gain for each frequency band at time t n as suggested by the present invention, here indicated by times t 1 , t 2 , t 3 and which may successively substitute the predefined maximum acceptable forward gain values IG max-FBM set by a hearing aid specialist (see later) or IG max-std as set by a manufacturer.
  • IG(t n ) Current insertion gain, IG(t n ), for a given frequency band k and point in time t n , termed IG k (t n ), is typically equal to the value of insertion gain for frequency band k as determined in the signal processor (here termed the 'requested insertion gain' IG req.k (t n )) based on the current input signal (including its level), the predefined compression scheme, the users audiogram, etc.
  • the current insertion gain for the band in question, IG k (t n ) can be modified subject to limitations based on the predefined maximum acceptable insertion gain IG max (pd) (or loop gain LG max (Pd)) as defined above OR according to later determined (and stored) values of maximum acceptable insertion gain, IG max,i (t n ), as described later.
  • a hearing aid system :
  • a hearing aid system comprising an input transducer, a forward path, an output transducer and an electrical feedback path
  • the forward path comprising a signal processing unit for modifying an electrical input signal to a specific hearing profile over a predefined frequency range, wherein the predefined frequency range comprises a number of frequency bands, for which at least maximum (allowable) forward gain values IG max for each band are or can be stored in a memory
  • the electrical feedback path comprising an adaptive filter for estimating acoustical feedback from the output to the input transducer.
  • the hearing aid system further comprises an online feedback manager unit (OFBM) for - with a predefined update frequency - identifying current feedback gain in each frequency band of the feedback path, and for subsequently adapting the maximum (allowable) forward gain values in each of the frequency bands in dependence thereof in accordance with a predefined scheme.
  • OFBM online feedback manager unit
  • the update frequency is smaller than 0.5 Hz or smaller than 0.1 Hz or smaller man 0.05 Hz or smaller than 0.01 Hz or smaller man 0.001 Hz corresponding to a relatively slow online feedback manager as described in more detail later.
  • the value of current feedback gain determined by the adaptive filter or the online feedback manager for a particular frequency band may vary across the frequency band.
  • any of the values for a given frequency band determined at a given point in time may be used (e.g. the value corresponding to the middle frequency of the band, or to the minimum or maximum frequency of the band or e.g. the minimum value of the band).
  • the 'current feedback gain' value used for a particular frequency band i is the maximum value of current feedback gain in the band at the actual point in time (t n ), FBG max,i (t n ).
  • the maximum value FBG max,i (t n ) in a set of feedback gain values FBG i (t n ) for a particular frequency band I may be determined e.g. by a standard software routine.
  • 'Offline' adjustment is taken to refer to adjustments made (infrequently, e.g. less man once a week or month) using external or additional instruments, e.g. at special occasions such as an initial or later fitting of the hearing aid, e.g. performed by another person (e.g. an audiologist) than the wearer of the hearing aid.
  • 'Online' adjustment is taken to refer to adjustments that can be made by the hearing aid itself, e.g. automatically or initiated by a wearer, e.g. in-situ, without any external instruments.
  • the term 'update frequency' in relation to the online feedback manager is taken to mean the frequency of checking the above criterion of 'identifying current feedback gain in each frequency band of the feedback path, and for subsequently adapting the maximum forward gain values in each of the frequency bands in dependence thereof in accordance with a predefined scheme'.
  • the storage of possible maximum forward gain values may be performed at the same or at a lower frequency than the update frequency, possibly depending on whether or not a change to a value of one or more of the frequency bands has occurred since the last check. In an embodiment, storage is performed every time at least one maximum forward gain value of a frequency band has been changed.
  • the parts of a hearing aid system according to the present invention are body worn and can be located in a common housing and e.g. worn behind the ear (BTE) or in the ear canal, or alternatively be located in different housings, one e.g. located in the ear canal another behind the ear or worn elsewhere on the body of the wearer.
  • the communication between the two or more housings can be acoustical and or electrical and/or optical.
  • the electrical and optical communication can be wired or wireless.
  • the input transducer and the processing unit are enclosed in the same physical unit and located e.g. behind an ear or in an ear canal.
  • Embodiments of an online feedback manager according to the invention can work in at least three different configurations. With or without an AFB system, and in a relatively fast or slow mode:
  • the online feedback manager continuously (i.e. with a certain update frequency) calculates the loop gain (e.g. based on an estimate of the current feedback gain from an adaptive filter and a requested current insertion gain from a signal processor) and adjusts the forward gain in the hearing aid so as to prevent the loop gain to exceed a certain (predefined) loop gain limit.
  • the OFBM must be fast enough to react to quickly changing feedback paths e.g.
  • the update frequency of the OFBM is larger than or equal to once every second (1 Hz), such as larger than or equal to 5 Hz, such as larger than or equal to 10 Hz. 2.
  • AFB system relatively fast online feedback manager.
  • the OFBM is working as a safety measure in cooperation with an AFB system.
  • AFB systems make it possible to increase the loop gain without introducing howls and artefacts, and it is possible to increase the loop gain above 0 dB.
  • the AFB will always be restricted, which means that the loop gain can not increase infinitely - the AFB system has a maximum loop gain under which it can operate (e.g. ⁇ +5 dB loop gain, i.e. LG max - +5 dB). If the loop gain exceeds this maximum, the OFBM will decrease the gain in the hearing aid so as to prevent conditions where the AFB system can not work acceptable.
  • the OFBM must be fast enough to react to quickly changing feedback paths e.g.
  • the update frequency of the OFBM is larger than or equal to once every hour, such as once every second (1 Hz), such as larger than or equal to 5 Hz, such as larger than or equal to 10 Hz.
  • This embodiment of the system can best be compared to an off-line feedback manager used in the fitting situation (i.e. occasionally).
  • the slow OFBM will slowly update the estimate made with the off-line feedback manager (of predetermined values of IG max,i and/or LG max,i ).
  • this system (3) is "preventive”: Reactive in the sense that the fast OFBM is active, when the loop gain gets too high. Preventive in the sense that the slow OFBM ties to avoid that the loop gain gets too high.
  • Target situations for this mode of operation are to deal with a) broken or badly fitted ear-moulds, b) wrong settings of the hearing aid (e.g.
  • the update frequency of the OFBM is larger than or equal to once every 100 hours, such as larger than or equal to once every 10 hours, such as larger than or equal to once every 2 hours, such as larger than or equal to once every hour.
  • the slow OFBM is adapted to accommodate changes in feedback that may occur during the day, e.g. due to minor changes in the 'local environment' of an earpiece due to a wearer's physical activity (e.g. resulting in sweat being produced in the ear canal), the ear canal exhibiting slight changes in dimensions, etc.
  • the predefined update frequency f upd is smaller than or equal to 0.01 Hz, such as smaller than or equal to 0.003 Hz.
  • the predefined update frequency of the OFBM is larger than or equal to once every 100 hours, while smaller than or equal to once every 5 minutes, i.e. 1/(100*60*60 s) ⁇ f upd ⁇ 1/(5*60 s), i.e. f upd is in the range from 2.78 ⁇ 10 -6 Hz to 3.33 10 -3 Hz.
  • the maximum gain values of the forward path IG max,i for a particular frequency band i are continuously updated (with the predefined update frequency) independently of current loop gain LG i in the band.
  • a relatively fast as well as a relatively slow OFBM is implemented in the same hearing aid system.
  • each of the relatively fast and relatively slow OFBM may be activated or deactivated by a software setting, in an embodiment, each may be activated or deactivated individually on a per frequency band level.
  • the relatively slow OFBM is dependent on the relatively fast OFBM In an embodiment, the relatively slow OFBM uses inputs from the relatively fast OFBM.
  • the target for the OFBM is either to reduce the risk of howling by decreasing the max insertion gain, or to increase the max insertion gain in situations where the risk of howling is reduced.
  • the system builds on an existing anti-feedback mechanism (max gain in forward path) but will make it adaptive/variable.
  • the OFBM makes it possible to increase or decrease the forward gain depending on the current situation.
  • the OFBM has only a direct effect on the current gain (IG i (t n )), when the requested gain (IG req,i (t n )) is above the maximum gain.
  • the OFBM system can either be preventive or reactive.
  • a preventive OFBM will continuously try to optimize the performance and reduce the risk of the OFC system being pushed too hard.
  • a reactive OFBM will try to help in situations where the DFC system has been pushed too hard and artefacts and bad sound quality are present.
  • the predefined scheme comprises that the maximum forward gain value for a frequency band is adapted so that the sum of the current feedback gain and the maximum forward gain values in that particular frequency band is smaller than a predefined maximum loop gain value for that band.
  • the maximum forward gain value is adapted so that the sum of the current feedback gain and the maximum forward gain values is equal to a predefined maximum loop gain value for that band.
  • the maximum forward gain value for a particular frequency band can be increased or decreased depending on the actual values of current feedback gain and the maximum loop gain values currently stored for that band.
  • the predefined maximum loop gam value is substantially identical for all frequency bands.
  • the predefined maximum loop gain value can be different from band to band or from a range of bands to another range of bands (e.g. from relatively low frequency bands to relatively high frequency bands).
  • different sets of predefined maximum loop gain values and/or predefined maximum allowable insertion gain values are stored corresponding to different modes of the OFBM, e.g. to a mode where the OFBM operates without an AFB-system in a relatively fast mode, to a mode where the OFBM cooperates with an AFB system in a relatively fast mode, and to a mode where the OFBM cooperates with an AFB system in a relatively slow mode.
  • the predefined scheme comprises that the maximum forward gain values for a// frequency bands are adapted every time the OFBM is updated.
  • the update frequency can be different for different frequency bands, e.g. relatively higher at frequency bands comprising relatively higher frequencies and relatively lower at frequency bands comprising relatively lower frequencies.
  • the OFBM can be selectably switched on or off for a particular frequency band.
  • a predefined maximum hop gain value LG max,i (pd) (which may be different from frequency band to frequency band) is +12 db, such as +10 dB, such as +5 dB, such as +2 dB, such as 0 dB, or such as -2 dB.
  • the (predefined) maximum loop gain LG max,i (pd) in a particular frequency band i is e.g. determined from an estimate of the maximum allowable loop gain before howling occurs (LG howl,i ) diminished by a predefined safety margin (LG margin ,i )-
  • the predefined maximum loop gain values LG max,i (pd) are determined on an empirical basis, e.g. from a trial and error procedure, e.g. based on a users typical behaviour (actions, environments, etc.).
  • the predefined frequency range is from 20 Hz to 20 kHz, such as from 20 Hz to 12 kHz, such as from 20 Hz to 8 kHz.
  • the predefined frequency range comprises at least 2 frequency bands, such as at least 4, such as at least 8, such as at least 12, such as at least 16, such as at least 32 bands.
  • the compression Is the same in all frequency bands.
  • compression is in the present context taken to refer to the phenomenon that the processing of an input signal is performed in such a way that a certain input level range is mapped to a smaller output level range than would otherwise have been set to compensate for the hearing loss of the user (i.e. the input signal is attenuated (compared to the, e.g. linear, mapping at relatively lower input levels) at a particular frequency, rf the input level at that frequency is above a predefined level).
  • the compression can be different in different frequency bands. This has the advantage that a more flexible adaptation to the frequency dependent hearing profile and level sensitivity of a particular user can be provided.
  • the update frequency is adapted to the relevant hearing situation, e.g. based on one or more particular sensors for classifying the present environment (e.g. directional microphones or external signals forwarding such information to the hearing aid) and/or based on recorded data of the frequency of howl appearing in a predefined time period, e.g. the last minute or the last 10 minutes or the last hour.
  • a predefined time period e.g. the last minute or the last 10 minutes or the last hour.
  • the order of the update frequency is in the once a second range, or in the once a minute range, or in the once an hour range or in the once every 10 hours range or in the once every 100 hours range.
  • the hearing aid system is adapted to provide an update frequency larger than or equal to 0.001 Hz, such as larger than or equal to 0.01 Hz, such as larger than or equal to 0.1 Hz, such as larger than or equal to 1 Hz, such as larger than or equal to 10 Hz, such as larger than or equal to 100 Hz, such as larger than or equal to 1 kHz.
  • the update frequency is in the range between 0.001 Hz and 1 kHz, such as in the range between 0.005 Hz and 0.05 Hz or between 0.5 Hz and 5 Hz or between 50 Hz and 500 Hz.
  • An OFBM according to the invention can be fully or partially implemented in a digital signal processor of the hearing aid system and can be fully or partially implemented in software.
  • IGma ⁇ -i or IG max Xpd
  • a relatively slow online feedback manager if a correspondingly low update frequency is chosen, e.g. fupd ⁇ 0,5 Hz. If the IGm 8x Xt n ) values are not stored and a relatively large update frequency (e.g. fup d > 1 Hz) is chosen, a relatively fast online feedback manager is implemented.
  • the hearing aid system is adapted to run the algorithm at different points in time ti, fc, ..., t n ,
  • t n -t n .1 (and Wt n ) represents a time interval between two updates of the OFBM.
  • 1/(WrW (•1/ftrVi)) represents an update frequency f ⁇ of the OFBM.
  • Predefined fade-rates FRj [db ⁇ ime step] for each frequency band are used.
  • FR is different for positive and negative changes to IG n ⁇ i. in an embodiment, the fade rate FRj.
  • step 4 the current maximum forward gain IGm U1i (t n ) is adapted to provide that the current maximum loop gain LGmwit n ) is smaller than fiie predefined maximum loop gain value LG ⁇ pd) for frequency band
  • step 4 the current maximum forward gain IGm ⁇ t n ) is adapted to provide that the current maximum loop gain LG max .,(t n ) is substantially equal to the predefined maximum loop gain value LGm «. i (pd) for frequency band i.
  • LG m ⁇ Xr r(pd) ⁇ 12 dB such as LG m * ⁇ ri (pd) ⁇ 10 dB, such as LGm ⁇ c i (pd) ⁇ 5 dB, such as ⁇ 4 dB, such as ⁇ 3 dB, such as ⁇ 2 dB, such as ⁇ 1 dB, such as ⁇ 0 dB, such as ⁇ -1 dB.
  • the algorithm is run at regular intervals in time, with a predefined update frequency W
  • fupo 1/(Wt n ).
  • a set of update values (of current feedback gain and/Or maximum forward gain) from a number of update times ti, fe, Vietnamese t, (possibly corresponding to a certain update frequency or to a number of non-periodic, e.g. user initiated, update times) are stored in a memory and an average value is calculated for the time period ti-tq and this value is used for the next period of time (e.g. of length tq-ti) ⁇ ⁇ ex which the values stored in the next period are averaged and so on.
  • the update frequency of the OFBM is adapted to the relevant situations where it can improve the performance, for example hug ( ⁇ 1 8.), chewing /yawning (-10 s.) F telephone (-1-10 mm.), putting on a hat (-1 hour), change of the mould/ear channel through the day ( « 10 hours), change of the mould/ear channel through days (-100 hours), where the times in parentheses represent typical times between updates for the situation in question (i.e. ⁇ 1/fup d ) in a particular embodiment, the update or update frequency of the OFBM can be activated or influenced by a user.
  • the update or update frequency of the OFBM is only activated or determined by a user, in a particular embodiment, the update or update frequency of the OFBM is activated or influenced by events in the acoustical environment of the hearing aid system, e.g. changing background noise or a change from sound without voice signals to sound including voice- signals (or vice versa), I an embodiment, the update or update frequency of the OFBM is activated or influenced by an external signal.
  • the external signal is forwarded to the hearing aid by a transmitter located in a particular acoustical environment, e.g. in a particular room of a building, in a transport facility, etc.
  • the effect of the OFBM is limited, e.g. to +/- 5 dB of the initial max gain, in a particular embodiment, the OFBM is constrained to a predefined maximum change, e.g. only to be allowed to make maximum of +/- 2 dBs of change. This has the advantage of reducing the risk of making too large and sudden changes (e.g. increases in gain). In a particular embodiment, the OFBM is constrained to only be able to decrease the max gain.
  • the effect of the OFBM is adapted to be frequency dependent in that the adjustment of maximum (and/or minimum) gain in at least one frequency band is different from other frequency bands.
  • the OFBM is adjustable in the fitting situations in that e.g. a choice between higher gain/higher risk of howls or lower gain/lower risk of howls can be made.
  • the OFBM is adapted to use information from other sub systems (e.g. environmental detectors or external signals indicating the kind or acoustical environment currently present) in the HA to increase the performance by making the decisions more confident (e.g. by influencing the update frequency).
  • a method of adapting a hearing aid system :
  • a method of adapting a hearing aid system to varying acoustical input signals comprising an input transducer transforming an acoustical input signal to an electrical input signal, a forward path, an output transducer for transforming an electrical output signal to an acoustical output signal and a feedback path, the forward path comprising a signal processing unit for modifying an electrical input signal to a specific hearing profile over a predefined frequency range, wherein the predefined frequency range comprises a number of frequency bands that can be individually adapted, the feedback path comprising an adaptive filter for estimating acoustical feedback from the output to the input transducer.
  • the method comprising a) identifying maximum feedback gain in each frequency band, b) calculating the (current maximum) loop gain in each of the frequency bands based on previously stored values of maximum forward gain and said maximum feedback gain, c) checking whether the (current maximum) loop gain is above a certain (predefined) maximum loop gain value in each frequency band, d1) if yes, decreasing the maximum forward gain in that frequency band, d2) if no, depending on a predefined first OFBM-parameter, increasing the maximum forward gain OR continue without changing the maximum forward gain in that frequency band, e) storing in a memory the new values of the maximum forward gain in each frequency band, f) repeating the algorithm a) - e) with a predefined update frequency.
  • the update frequency is smaller than 0.5 Hz or smaller than 0.1 Hz or smaller man 0.05 Hz or smaller than 0.01 Hz or smaller than 0.001 Hz corresponding to a relatively slow online feedback manager.
  • the maximum forward gain is decreased or increased with a predefined amount, e.g. 0.5 dB, 1 dB or 2 dB.
  • step d) the maximum forward gain is decreased or increased at most to a predetermined fraction of (such as down or up to) said predetermined maximum loop gain value in each frequency band.
  • the predetermined maximum loop gain values are identical in all frequency bands. They might alternatively be different for some or all bands.
  • a method of manufacturing a hearing aid system :
  • a method of manufacturing a hearing aid system comprising a) providing an input transducer for transforming an acoustical input signal to an electrical input signal, b) providing an output transducer for transforming an electrical output signal to an acoustical output signal, c) providing an electrical forward path between the input and output transducers, the forward path comprising a signal processing unit for modifying an electrical input signal to a specific hearing profile over a predefined frequency range, and providing that the input signal can be individually adapted in a number of frequency bands included in the predefined frequency range, d) providing an electrical feedback path comprising an adaptive filter for estimating acoustical feedback from the output to the input transducer, e) providing an algorithm for adjusting the gain in the forward path, the algorithm comprising e1 ) identifying the maximum feedback gain in each frequency band, e2) calculating the (current maximum) loop gain in each of the frequency bands based on previously stored values of maximum forward gain and said maximum feedback gain, e
  • a software program stored on a computer readable medium is moreover provided by the present invention.
  • the software program When executed on a signal processing unit of a hearing aid system as described above, the software program implements one or more (such as a majority or all) of the steps of the method of adapting a hearing aid system as described above.
  • FIG. 1 shows the forward path of an exemplary hearing aid (FIG. 1a), the forward path and an electrical feedback cancellation path of an exemplary hearing aid (FIG. 1b), and a part of a hearing aid comprising an Online Feedback Manager (OFBM) according to an embodiment of the invention (FIG. 1c).
  • OFBM Online Feedback Manager
  • FIG. 2 shows a loop gain vs. normalized frequency curve for a hearing aid system according to an embodiment of the invention comprising an online feedback manager unit OFBM1 used as an AFB system without a dedicated DFC system.
  • FIG. 3 shows a loop gain vs. normalized frequency curve for a hearing aid system according to an embodiment of the invention comprising an online feedback manager unit OFBM 1 used as an AFB system combined with a DFC system.
  • FIG. 4 shows a loop gain vs. normalized frequency curve for a hearing aid system according to an embodiment of the invention comprising an online feedback manager unit OFBM2 used as feedback limiter.
  • FIG. 5 shows a loop gain vs. normalized frequency curve for a hearing aid system according to an embodiment of the invention comprising an online feedback manager unit OFBM3 used as feedback optimizer in a case of too low maximum gain.
  • FIG. 6 shows a loop gain vs. normalized frequency curve for a hearing aid system according to an embodiment of the invention comprising an online feedback manager unit OFBM3 used as a feedback optimizer in a case of too high maximum gain.
  • FIG. 7 is a sketch of different settings of the maximum forward gain IGm*x vs. frequency for an embodiment of a hearing aid system according to the invention
  • FIG. 8 shows the influence of maximum insertion gain IGm 4x on current insertion gain IG (here shown in a continuous picture; in practice the frequency range is divided into a number of bands as illustrated in FIG. 7), where IG is automatically adjusted according to IG max - The resulting IG is represented by thick lines.
  • FIG. 9 illustrates a situation where more gain is supplied to the user, when tile OFBM is updated resulting in an increase in IG max .
  • FIG. 10 illustrates a situation when the OFBM is updated resulting in a decrease in IG ⁇ x .
  • FIG. 11 shows an example of daily varying IG max as found by an embodiment of the fast OFBM according to the invention. Examples of maximum (upper solid curve) and minimum limits (lower solid curve) of IG ⁇ MX (as e.g. allowed by an audkrfogist) are indicated.
  • the dotted curve may represent IGm** as determined by an automated procedure during fitting (e.g. by a software programming tool).
  • FIG. 12 shows a block diagram of a part of an embodiment of a hearing aid comprising an OFBM according to the present invention.
  • FIG. 13 illustrates the combined effects of a fast and slow OFBM according to an embodiment of the present invention.
  • Upper curves represent IG ⁇ when initially or preliminary fitted or estimated (dotted curve) and accepted maximum (max, high ⁇ and minimum (max, low) limits e.g. as determined by an audiologist (solid curves) are used.
  • Lower curves represent IG max after some time (weeks and months) also with maximum and minimum limits.
  • FIG. 1 shows the basic components of a hearing aid system 100.
  • FIG. 1a illustrates the forward path and an (unintentional) acoustical feedback path of a hearing aid.
  • the forward path comprises an input transducer for receiving an acoustic input from the environment, an AD-oonverter, a processing part HA-DSP for adapting the signal to the needs of a wearer of the hearing aid, a ⁇ -converter (optional) and an output transducer for generating an acoustic output to the wearer of the hearing aid.
  • the intentional forward or signal path and components of the hearing aid are enclosed by the dashed outline denoted 100.
  • An (external, unintentional) acoustical feedback path ACFB from the output transducer to the input transducer is indicated.
  • FIG. 1b illustrates a hearing aid 100 as in FIG. 1a, additionally comprising an electrical feedback cancellation path for reducing or cancelling acoustic feedback from an 'external' feedback path from output to input transducer of the hearing aid (termed 'Acoustic Feedback in FIG. 1b).
  • the electrical feedback cancellation path comprises an adaptive filter, which is controlled by a prediction error algorithm, e.g. an LMS (Least Means Squared) algorithm, in order to predict and cancel the part of the microphone signal that is caused by feedback from the receiver of the hearing aid.
  • the adaptive filter (in FIG.
  • the forward path (alternatively termed 'signal path') of the hearing aid comprises signal processing (termed 'HA-DSP in FIG. 1b) to adjust the signal to the (possibly impaired) hearing of the user.
  • the functional parts of the present invention preferably form part of the loop constituted by the forward path and the electrical feedback path and can e.g. be an integral part of the processing unit (HA-DSP in FIG. 1b) or the adaptive filter (possibly all located on the same integrated circuit). Alternatively, they may be implemented partially or fully separate there from.
  • FIG. 1c shows a part a hearing aid comprising an Online Feedback Manager ( 1 OFBM in FIG. 1c) according to an embodiment of the invention.
  • FIG. 1c illustrates a forward path comprising a forward gain block G(z) defining a maximum gain, an acoustical feedback path comprising a feedback contribution H(z), and a (electrical) feedback path comprising an adaptive filter for calculating an estimate H'(z) of the acoustical feedback, the latter e.g. forming part of a conventional DFC system.
  • the OFBM uses the feedback path estimate from the DFC system to calculate the maximum forward gain.
  • the (current) forward gain is calculated by the compression system (signal processor, forward gain block G(z)).
  • fm* can be between 5 and 50 Hz, e.g. 20 Hz and f max between 8 kHz and 25 kHz, e.g. 12 kHz and the number of frequency bands alternatively be any appropriate number, e.g.4 or 16 or 24 or 32 or 64 or 128 or larger.
  • the graph !Gma**t d indicates a standard setting of the maximum allowable forward gain for the different frequency bands, such as e.g. the (relatively conservative) setting of a hearing aid system directly from the manufacturer.
  • IG ⁇ N M-FBM indicates a setting (predefined values (pd)) of maximum allowable forward gain, such as e.g. adapted by an audiologist using an offline feedback manager' (or using an automated procedure, e.g. a software tool running on a PC) to adjust the settings to a hearing profile of a given user.
  • the graphs IGnu ⁇ oFBtrft n ) schematically indicate stored values of the maximum allowable forward gain for each frequency band at time t n as suggested by the present invention, here indicated by times ti, t 2 , U-
  • the feedback limits in a hearing aid can be defined by the IGm 4x (maximum insertion gain) parameters.
  • a total of N IGm» parameters are available - one for each frequency band, where N is the number of frequency bands.
  • the target value and a fade-rate can be defined (the target value being the IG ⁇ t n ) value determined by the OFBM at a given point in time t n , and the fade-rate being the rate FRf (for the i* frequency band) at which currently applied IGm W j(Vi) (appropriately faded) values converge (fades') towards the target value IG m «,j(t n ).
  • the feedback limits FBG fTMK are typically defined during the fitting process -as pre- ⁇ cribed (predefined) values based on characteristics of the actual hearing instrument, including the size of a possible vent. etc.
  • the maximum feedback values applied are often a rather conservative estimate, and are typically several dB above the actual feedback limit, in order to account for variations in the user environment.
  • the use of an OFBM according to the present invention enables the use of less conservative estimates and thereby extending the fitting range of the hearing aid.
  • the idea behind the OFBM is to control the !G max , which is used to limit insertion gain (IG) available for the wearer of the hearing aid according to the current user situation.
  • IG insertion gain
  • FB feedback
  • FIG. 8 shows the resulting IG, partly as prescribed IG, and parity as individual IG 1 if the wearer wishes more gain than prescribed.
  • the OFBM will continuously update the IGm M according to the user situation.
  • the OFBM may change IGm ⁇ x in direction of more gain, see FIG. 9. The consequence may be that gain for the user will be higher. It should be noted, though, that this is not necessarily of benefit in all situations since more gain make sounds become more dominating and perhaps with poor sound quality since headroom (compression and Maximum Power Output (MPO)) is not increased in same manner. Therefore, the audiologist needs to define an upper limit for the IGmm of the OFBM (not shown in FIG. 9).
  • the OFBM may decrease FBGmw or IGm** for example when the ear mould is not mounted correctly in the ear, see FIG. 10.
  • the gain available for the user may be so low that some sounds become inaudible.
  • a minimum limit for FBG n ⁇ x or IGm n of the OFBM can be implemented (not shown in FIG. 10).
  • the OFBM may not be able to suppress the howling due to this minimum limit, but the occurrence of howl will remind the user or the care keeper to reinsert the ear mould in a correct manner.
  • FIG. 12 schematically shows a block diagram of parts of an embodiment of a hearing aid system 100 comprising an anti feedback system (AFB) 110 and an OFBM (comprising a Fast OFBM 150 and a Slow OFBM 160) according to the present invention.
  • the Fast OFBM 150 uses input 111 from the AFB- system 110 (e.g. loop gain calculation, feedback and leak detection) to calculate ('IG max CTRL' in FIG. 12) new target values and fade rates 151 for the N (e.g.
  • the Slow OFBM 160 continuously logs (togging' in FIG. 12) the correction of IG max from the fitted values and calculates a time average for each of the N (e.g. 16) frequency bands. These average values 161 are then used to update the target values for IG m «, here shown as signals 162 from a learning' module to the IGm 4x CTR-block.
  • Optional detectors 170 e.g. directionality detector, mode detector, volume control, acoustic environment detector, location detector, etc.
  • the hearing aid system 100 may form part of the hearing aid system 100 or be external to the hearing aid system are shown providing inputs 171 to the Fast and/or Slow OFBM units.
  • FIG. 12 a Fast and Slow OFB are shown to work in cooperation. Alternatively each of them may be used alone.
  • the hearing aid system 100 is shown to be connectable to an external 'offline' FeedBack Manager 200 ('FBM' in FIG. 12), e.g. indicating a software tool (e.g. run on a PC) of an audtologist for making a fitting of the hearing aid system to a wearer's needs.
  • 'FBM' in FIG. 12 e.g. indicating a software tool (e.g. run on a PC) of an audtologist for making a fitting of the hearing aid system to a wearer's needs.
  • Data 163 from the logging system of the Slow OFBM 160 including logged IG max values for each frequency band and for a number of different points in time may be forwarded to the FBM for further analysis.
  • Optional connection 201 is indicated for forwarding data from the FBM to the OFBM, e.g.
  • the communication between the hearing aid system 100 and optional external detectors 170 or programming units 200 or other devices may be wired or wireless and based on electrical or optical signals.
  • tiie average correction exceeds a certain threshold, indications could be given to the wearer in the form of beeps or blinks.
  • the OFBM can be adapted to accept inputs from other detectors in the system in order to obtain the desired functionality.
  • Each of the three OFBM blocks will be treated separately in the following sections.
  • the Fast OFBM is a system that updates IG max , e.g. once every second. If the update speed becomes much slower (e.g. more than 5 - 10s between updates) interaction from other automatic features in the HA (directional microphone system, learning modes, etc.) will influence the OFBM performance.
  • the Fast OFBM works more or less in the same way as a feedback manager of a software programming tool, such as e.g. used by an audioiogist when adapting a hearing instrument to a particular wearers needs. It attacks the problem that causes AFB problems directly; namely the foop gain. Loop gain is the sum of the gain in the feedback path and the gain in the signal path and when this value gets too large, the HA starts to sound "bad", and when the value surpasses 0 dB, the HA is likely to howl.
  • the goal of the OFB is to keep the AFB within the interval of loop gains that can be handled by the AFB system.
  • LG(f) HoFc( ⁇ +Hsp(f)
  • HDFC is the feedback estimate of the AFB-system
  • H$p is the signal processor gain.
  • the practical implementation of the HQFC and HSP transfer functions can comprise FIR- or IIR-filters or any other appropriate components.
  • a method which will restrict loop gain to a specified maximum value can be implemented. Such a method both prevents feedback howls from occurring and eliminates feedback howls after they occur and comprises: a) in a static situation, determine (in each frequency interval) the critical (maximum) loop gain to avoid howling LG hO w ⁇ , which can be handled by the AFB system, b) Decide an appropriate gain margin in each frequency band and subtract this value from corresponding LG h0 * ⁇ values, resulting in values for the maximum allowed loop gain LGm 4x for each frequency band. To enforce this loop gain we would then perform the following steps for each of the frequency intervals (e.g. 16).
  • IG n ⁇ LG mBX - AFlW
  • threshold values restricting the interval wherein IGW can be adjusted are defined (lIGnwchs ⁇ hl IG max .towJ)- This limits the influence of the AFBm ⁇ values, which may be relatively inaccurate.
  • the value, which is calculated and applied to IGm* is applied to the target IGm 8x ; the actual IG m ⁇ x used by the hardware, current IG max , fades towards this value. This will keep the OFBM stable.
  • the fade rates should preferably be adjusted so that the OFBM can reduce gain relatively quickly and increase gain over a longer time interval.
  • Stow OFBM (in addition to a Fast OFBM)
  • the Stow OFBM continuously logs data from the Fast OFBM and uses this as input to a learning routine.
  • the adaptation of the Stow OFBM is much slower than the Fast OFBM.
  • the adjustments made to IGm 89 may be greater than what the Fast OFBM does.
  • FIG. 13 illustrates the combined effects of a fast and stow OFBM according to an embodiment of the present invention.
  • Upper curves represent IG m , x when initially or preliminary fitted or estimated (dotted curve) and accepted maximum and minimum limits e.g. as determined by an audiologist (solid curves).
  • Lower curves represent IGm 8x after some time (weeks and months) also witti maximum and minimum limits.
  • the difference between upper and lower curves is due to an adaptation process of the slow OFBM, and the gain change velocity (dB ⁇ veek) of the adaptation is e.g. specified by the audiologist (e.g. maximum gain reduction of 1 dB/week, such as 2 dB a week, such as 3 dB/week) during an initial or later fitting of the system using an off-line feedback manager tool.
  • the stow OFBM system is based upon input from a statistical surveillance of the fast OFBM system. It can advantageously be applied in connection with ear moulds for children, which gradually become too small. Contrary to a wrongly inserted ear mould, this condition wilt be handled by the fast OFBM as long as it can reduce gain within the allowed attenuation limit minjgmaxjhresholds (cf. table above). However, as the mould gets looser, a further reduction may be needed as well as a decreased defaultjgmaxjhreshold (cf. e.g. dotted line in FIG. 13). The default values and lower limit values would then be updated with new settings (both saved in a memory, e.g. an EEPROM, of the system). The upper limits/gain margin is preferably also updated towards less allowed ⁇ G max
  • Information may be passed on to a warning system that is responsible for notifying the user or another relevant person about the problem.
  • the system is preferably configurable so that it can selectably:
  • the slow OFBM only updates EEPROM settings (e.g. defautt_igmax_threshold), i.e. the effect of the slow OFBM is only applied to the gain path after a boot of the processor or a program change.
  • User information may be given at any time, i.e. not only at start-up.
  • the slow OFBM may be considered equivalent to an audiologist renewing the fitting once at a week. It has the advantage of avoiding a time consuming refitting by an audiologist, which is in general would not be practical at such a high frequency.
  • a wearer at least one with severe/profound hearing loss : is assumed to use the hearing aid every day, and therefore reboots the hearing aid system every morning or when being aided with the hearing aid. Accordingly, the wearer will not notice immediately the gain change (e.g. with max 2 dB change a week since this would correspond to ⁇ ' dB change a day). Information from a wearer may be fed into the system.
  • One or more of the following parameters are preferably added for improved function of the slow OFBM:
  • the default settings of gain characteristics of the hearing aid are preferably updated in upwards or downward direction in accordance with predefined rules in dependence on selected learning principles.
  • a histogram of the number of bands truncated by a limit at each update for the fast OFBM is produced. This histogram represents the likelihood of a given number of bands in need for a larger IG max change than allowed. If the histogram median is high (larger than a predefined value), a learning update is needed. Learning updates and histogram scaling (forgetting) are preferably done at regular (predefined) intervals in time. Separate histograms for upwards and downwards learning are preferably produced.
  • the average I ⁇ max changes relative to the default value for each band are logged, if the average exceeds a predefined threshold value, a learning step is performed, if it is within (predefined) dynamic range constraints of other (e.g. adjacent) bands. Learning-updates and average scaling (forgetting) are preferably done at regular (predefined) intervals in time.
  • Example 1 OFBM 1. use of an (relatively fast) OFBM as an AFB-svstem:
  • the OFBM 1 is able to work as an (standalone) AFB system, if the target (predefined gain limit) for the OFBM 1 is ⁇ Q dB loop gain and the system has a relatively fast update speed of e.g. 100 ms (i.e. an update frequency around 10 Hz). The closer the target loop gain is to 0 dB the faster a system is needed (the higher the update frequency). If the target is below 0 dB loop gain, the DFC system can be bypassed and only used for estimating the feedback path (cf. FIG. 2).
  • FIG. 2 shows a loop gain vs. normalized frequency curve for a hearing aid according to an embodiment of the invention comprising an online feedback manager unit OFBM 1 used as an AFB system without a dedicated DFC system.
  • the normalized frequency range corresponds to a real frequency range of e.g. 20 Hz to 12 kHz.
  • the OFBM1 system uses the feedback estimate to control the maximum gain of the feedback loop.
  • the DFC is not needed, because the feedback is removed by gain reduction.
  • a slower system lower update frequency
  • needs a tower threshold lower predefined gain limit
  • FIG. 3 shows a loop gain vs. normalized frequency curve for a hearing aid according to an embodiment of the invention comprising an online feedback manager unit OFBM1 used as an AFB system combined with a DFC system.
  • the target predefined gain limit
  • the DFC system is still needed, but the working interval of the OFBM will be constrained to a predefined loop gain limit, e.g. maximum 3 dB loop gain, because the OFBM1 will continuously (i.e. with a certain update frequency) reduce the forward gain to achieve maximum 3 dB loop gain (cf. FIG. 3).
  • a predefined loop gain limit e.g. maximum 3 dB loop gain
  • the OFBM1 will continuously (i.e. with a certain update frequency) reduce the forward gain to achieve maximum 3 dB loop gain (cf. FIG. 3).
  • the threshold feedback is removed by gain reduction. Between 0 dB loop gain and the threshold, feedback is removed using the DFC.
  • the OFBM will work as a stand-alone AFB system (if the target is ⁇ 0 dB and the DFC system is used for feedback estimation only) or as a parallel system to the DFC system (if the target is > 0 dB loop gain), in both setups the OFBM1 will have a major impact on the forward gain and will depend on a reliable feedback path estimate from the DFC system.
  • the OFBM1 will reduce the gain where the loop gain is above the limit, and reducing the gain will make it more difficult for the DFC system to estimate the feedback path in that region.
  • the OFBM will always be slower than the DFC system and will decrease the gain after the DFC system has estimated the feedback path and removed the feedback signal.
  • the coefficients from the DFC system are used to calculate the frequency response in a processor and from the frequency response the maximum feedback in each band are found. This maximum feedback determines the maximum gain in the forward path.
  • the OFBM is constrained to a predefined maximum allowed change per update, e.g. only allow +/- 2 dBs of change.
  • a predefined maximum allowed change per update e.g. only allow +/- 2 dBs of change.
  • the OFBM can be used to limit the maximum loop gain.
  • the working interval for the DFC system is from -• dB to + « ° dB loop gain. This interval is difficult to handle, and it is well known that a working interval from about 0 dB to 12 dB loop gain is the optimum for the OFC system.
  • Using the OFBM to limit the maximum loop gain ensures that the DFC system will not be pushed too much: If the loop gain increases above the limit (predefined gain limit), the forward gain will be reduced and thus increase the ability for the DFC system to remove the feedback. This can be seen as changing the working interval for the DFC from - « dB to +* dB loop gain to e.g.
  • FIG. 4 shows a loop gain vs. normalized frequency curve for a hearing aid according to an embodiment of fiie invention comprising an online feedback manager unit OFBM2 used as feedback limiter. If the loop gain exceeds the threshold (predefined gain limit), the gain is reduced.
  • the OFBM will only be active in situations where the user will experience artefacts and bad sound quality, because of too high loop gain and a DFC system that is pushed too hard.
  • the gain will be reduced but only in situations where the user has no twe ⁇ of it.
  • the OFBM2 is not dependent on a reliable estimate each 100 ms, but can wait to certain requirements are fulfilled, such as a minimum variation in the feedback estimate, detectors, or similar indicators of the reliability of the estimated feedback.
  • the OFBM3 can be seen as an adaptive addition to the initial max gain IGm n set during an initial (or later) fitting procedure (e.g. by an audiologist). It is known that the feedback path will change over time as a result of the different conditions through the day or days. The target of the OFBM3 is to slowly update the max gain to follow these changes.
  • FIG. 5 shows a loop gain vs. normalized frequency curve for a hearing aid according to an embodiment of the invention comprising an online feedback manager unit OFBM3 used as feedback optimizer in a case of too low maximum gain.
  • the maximum gain is too restrictive, so the user might not get the wanted gain.
  • FIG. 6 shows a loop gain vs. normalized frequency curve for a hearing aid according to an embodiment of the invention comprising an online feedback manager unit OFBM3 used as a feedback optimizer in a case of too high maximum gain, if a sudden increase in the feedback path occurs, the loop gain can get too high for the DFC system.
  • the OF BM 3 is based on the assumption that it is possible to get a reliable feedback estimate on average over time, e.g. several minutes (the update frequency is e.g. smaller than or equal to 0.01 Hz). If mis assumption is met, the OFBM3 could relax the safety margin used when presetting the max gain of the hearing aid.
  • OFBM3 updates lew j continuously (i.e. with the predefined update frequency) independent of the loop gain LGi.
  • the other OFBM systems (OFBM 1, OFBM2) only update current insertion gain IG (J n ) when the loop gain exceeds a chosen threshold (predefined loop gain limit LG n ⁇ i).
  • the averaged estimated feedback path is affected by tonal input small gain, or quick changes in the feedback path.
  • DIRectfonalfty a functional block that shifts between an omni-directional mode (having a substantially equal sensitivity to sounds at ail spatial angles) and a directional mode (having a better sensitivity at one or more preferred spatial angles (e.g. best sensitivity for sounds coming from one particular angle, e.g. from in front).
  • Shifts in the ADIR have time constants of the order of seconds, e.g. 3-4 s, so the OFBM is preferably able to accommodate such time constants (be fast enough), e.g. 0.5 Hz ⁇ f ⁇ ⁇ 0.1 Hz.

Landscapes

  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Neurosurgery (AREA)
  • Otolaryngology (AREA)
  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Tone Control, Compression And Expansion, Limiting Amplitude (AREA)
  • Circuit For Audible Band Transducer (AREA)
  • Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)

Abstract

L'invention concerne un système d'aide auditive comprenant un transducteur d'entrée, un trajet direct, un transducteur de sortie et un trajet de rétroaction électrique, le trajet direct comprenant une unité de traitement de signal pour modifier un signal d'entrée électrique en un profil auditif spécifique sur une plage de fréquences prédéfinie, la plage de fréquences prédéfinie comprenant un certain nombre de bandes de fréquence, pour laquelle des valeurs de gain direct maximal IG^3x pour chaque bande peuvent être stockées dans une mémoire, le trajet de rétroaction électrique comprenant un filtre adaptatif pour estimer une réinjection acoustique du transducteur de sortie dans le transducteur d'entrée. L'invention concerne en outre un procédé d'adaptation d'un système d'aide auditive à divers signaux d'entrée acoustiques. L'objectif de la présente invention est de proposer un autre système de compensation de réinjection acoustique (larsen). L'objectif est atteint par le fait que le système d'aide auditive comprend en outre une unité de gestion de rétroaction en ligne - avec une fréquence de mise à jour prédéfinie - pour identifier un gain de rétroaction réel dans chaque bande de fréquence du trajet de rétroaction, et pour adapter ensuite les valeurs de gain direct maximal dans chacune des bandes de fréquence en fonction de ce gain selon un schéma prédéfini. Cela offre l'avantage de réduire la probabilité d'un larsen gênant et d'améliorer l'annulation de la réinjection. L'invention peut par exemple être utilisée dans des prothèses auditives numériques à utiliser dans des environnements acoustiques divers.
EP08760480.7A 2007-06-12 2008-06-04 Système anti-larsen en ligne pour une prothèse auditive Active EP2160922B1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
DK12162551.1T DK2533551T3 (en) 2007-06-12 2008-06-04 Online anti-feedback system for a hearing aid
EP12162551.1A EP2533551B1 (fr) 2007-06-12 2008-06-04 Système anti-feedback en ligne pour appareil d'aide auditive
EP08760480.7A EP2160922B1 (fr) 2007-06-12 2008-06-04 Système anti-larsen en ligne pour une prothèse auditive

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP07110079.6A EP2003928B1 (fr) 2007-06-12 2007-06-12 Système anti-feedback en ligne pour appareil d'aide auditive
PCT/EP2008/056898 WO2008151970A1 (fr) 2007-06-12 2008-06-04 Système anti-larsen en ligne pour une prothèse auditive
EP08760480.7A EP2160922B1 (fr) 2007-06-12 2008-06-04 Système anti-larsen en ligne pour une prothèse auditive

Related Child Applications (3)

Application Number Title Priority Date Filing Date
EP12162551.1A Division EP2533551B1 (fr) 2007-06-12 2008-06-04 Système anti-feedback en ligne pour appareil d'aide auditive
EP12162551.1A Previously-Filed-Application EP2533551B1 (fr) 2007-06-12 2008-06-04 Système anti-feedback en ligne pour appareil d'aide auditive
EP12162551.1A Division-Into EP2533551B1 (fr) 2007-06-12 2008-06-04 Système anti-feedback en ligne pour appareil d'aide auditive

Publications (2)

Publication Number Publication Date
EP2160922A1 true EP2160922A1 (fr) 2010-03-10
EP2160922B1 EP2160922B1 (fr) 2018-08-08

Family

ID=38656729

Family Applications (4)

Application Number Title Priority Date Filing Date
EP07110079.6A Active EP2003928B1 (fr) 2007-06-12 2007-06-12 Système anti-feedback en ligne pour appareil d'aide auditive
EP18187832.3A Active EP3429232B1 (fr) 2007-06-12 2007-06-12 Système anti-feedback en ligne pour appareil d'aide auditive
EP08760480.7A Active EP2160922B1 (fr) 2007-06-12 2008-06-04 Système anti-larsen en ligne pour une prothèse auditive
EP12162551.1A Not-in-force EP2533551B1 (fr) 2007-06-12 2008-06-04 Système anti-feedback en ligne pour appareil d'aide auditive

Family Applications Before (2)

Application Number Title Priority Date Filing Date
EP07110079.6A Active EP2003928B1 (fr) 2007-06-12 2007-06-12 Système anti-feedback en ligne pour appareil d'aide auditive
EP18187832.3A Active EP3429232B1 (fr) 2007-06-12 2007-06-12 Système anti-feedback en ligne pour appareil d'aide auditive

Family Applications After (1)

Application Number Title Priority Date Filing Date
EP12162551.1A Not-in-force EP2533551B1 (fr) 2007-06-12 2008-06-04 Système anti-feedback en ligne pour appareil d'aide auditive

Country Status (5)

Country Link
US (2) US8503705B2 (fr)
EP (4) EP2003928B1 (fr)
CN (1) CN101836465B (fr)
DK (4) DK3429232T3 (fr)
WO (1) WO2008151970A1 (fr)

Families Citing this family (37)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006042083B4 (de) 2006-09-07 2010-11-11 Siemens Audiologische Technik Gmbh Verfahren und Vorrichtung zur Bestimmung eines effektiven Vents
EP2003928B1 (fr) * 2007-06-12 2018-10-31 Oticon A/S Système anti-feedback en ligne pour appareil d'aide auditive
US9129291B2 (en) * 2008-09-22 2015-09-08 Personics Holdings, Llc Personalized sound management and method
WO2010088960A1 (fr) 2009-02-06 2010-08-12 Oticon A/S Substitution de bande spectrale pour éviter des sifflements d'accrochage et une sous-oscillation
DK2217007T3 (da) * 2009-02-06 2014-08-18 Oticon As Høreapparat med adaptiv tilbagekoblingsundertrykkelse
WO2010112073A1 (fr) 2009-04-02 2010-10-07 Oticon A/S Annulation adaptative d'échos sur des caractéristiques introduites ou intrinsèques, et récupération correspondante
DE102009051200B4 (de) * 2009-10-29 2014-06-18 Siemens Medical Instruments Pte. Ltd. Hörgerät und Verfahren zur Rückkopplungsunterdrückung mit einem Richtmikrofon
US9729976B2 (en) 2009-12-22 2017-08-08 Starkey Laboratories, Inc. Acoustic feedback event monitoring system for hearing assistance devices
WO2010040863A2 (fr) * 2010-01-15 2010-04-15 Phonak Ag Procédé d'utilisation d'un dispositif auditif et ce dispositif auditif lui-même
NL2004294C2 (en) * 2010-02-24 2011-08-25 Ru Jacob Alexander De Hearing instrument.
US9654885B2 (en) 2010-04-13 2017-05-16 Starkey Laboratories, Inc. Methods and apparatus for allocating feedback cancellation resources for hearing assistance devices
DK2439958T3 (da) * 2010-10-06 2013-08-12 Oticon As Fremgangsmåde til bestemmelse af parametre i en adaptiv lydbehandlings-algoritme og et lydbehandlingssystem
KR101812655B1 (ko) * 2011-02-25 2017-12-28 삼성전자주식회사 음원재생장치, 음원재생장치에서 음원을 재생하는 방법 및 궤환신호를 제거하는 방법
EP2523471B1 (fr) 2011-05-09 2014-06-18 Bernafon AG Système de test permettant d'évaluer la performance de rétroaction d'un dispositif d'écoute
DK2613567T3 (da) 2012-01-03 2014-10-27 Oticon As Fremgangsmåde til forbedring af et langtidstilbagekoblingsvejestimat i en lytteanordning
DK2613566T3 (en) 2012-01-03 2016-10-17 Oticon As A listening device and method for monitoring the placement of an earplug for a listening device
US9148734B2 (en) * 2013-06-05 2015-09-29 Cochlear Limited Feedback path evaluation implemented with limited signal processing
US9997171B2 (en) 2014-05-01 2018-06-12 Gn Hearing A/S Multi-band signal processor for digital audio signals
DK2988529T3 (da) 2014-08-20 2020-02-24 Sivantos Pte Ltd Adaptiv opdelingsfrekvens i hørehjælpeapparater
DK3002959T3 (en) * 2014-10-02 2019-04-29 Oticon As FEEDBACK ESTIMATION BASED ON DETERMINIST SEQUENCES
EP3016407B1 (fr) 2014-10-28 2019-12-11 Oticon A/s Système auditif pour estimer un trajet de rétroaction d'un dispositif auditif
US10105539B2 (en) 2014-12-17 2018-10-23 Cochlear Limited Configuring a stimulation unit of a hearing device
US10158953B2 (en) * 2015-07-02 2018-12-18 Gn Hearing A/S Hearing device and method of updating a hearing device
EP3139636B1 (fr) * 2015-09-07 2019-10-16 Oticon A/s Dispositif auditif comprenant un système d'annulation de rétroaction sur la base d'une relocalisation de l'énergie d'un signal
DK3148214T3 (da) * 2015-09-15 2022-01-03 Oticon As Høreanordning der omfatter et forbedret feedback-annulleringssystem
EP3185589B1 (fr) 2015-12-22 2024-02-07 Oticon A/s Dispositif auditif comprenant un système de commande de microphone
DK3249955T3 (da) * 2016-05-23 2019-11-18 Oticon As Konfigurerbart høreapparat, der omfatter en stråleformerfiltreringsenhed og en forstærkerenhed
EP3979667A3 (fr) * 2016-08-30 2022-07-06 Oticon A/s Dispositif auditif comprenant une unité de détection de rétroaction
US10751524B2 (en) * 2017-06-15 2020-08-25 Cochlear Limited Interference suppression in tissue-stimulating prostheses
DK3481085T3 (da) * 2017-11-01 2020-11-30 Oticon As Tilbagekoblingsdetektor og en høreanordning, der omfatter en tilbagekoblingsdetektor
DK3525489T3 (da) 2018-02-09 2021-07-05 Oticon As Fremgangsmåde til tilpasning af en høreanordning til en brugers behov, programmeringsanordning og høresystem
DE102018208657B3 (de) * 2018-05-30 2019-09-26 Sivantos Pte. Ltd. Verfahren zur Verringerung eines Auftretens einer akustischen Rückkopplung in einem Hörgerät
WO2020051593A1 (fr) 2018-09-07 2020-03-12 Dolby Laboratories Licensing Corporation Détection et suppression d'instabilité de superposition environnementale dynamique dans des dispositifs d'intercommunication au moyen d'une compensation multimédia
EP3703391A1 (fr) * 2019-02-27 2020-09-02 Oticon A/s Dispositif auditif comprenant un limiteur de gain de boucle
US11184713B2 (en) * 2019-11-19 2021-11-23 Sonova Ag Systems and methods for adjusting a gain limit of a hearing device
CN112866873B (zh) * 2020-12-30 2022-12-27 西安讯飞超脑信息科技有限公司 抑制啸叫的方法及相关模型的训练方法和设备、介质
EP4171070A1 (fr) 2021-10-19 2023-04-26 Oticon A/s Dispositif auditif comprenant un système de commande de rétroaction

Family Cites Families (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5091952A (en) * 1988-11-10 1992-02-25 Wisconsin Alumni Research Foundation Feedback suppression in digital signal processing hearing aids
DK169958B1 (da) 1992-10-20 1995-04-10 Gn Danavox As Høreapparat med kompensation for akustisk tilbagekobling
US6219427B1 (en) 1997-11-18 2001-04-17 Gn Resound As Feedback cancellation improvements
US6480610B1 (en) 1999-09-21 2002-11-12 Sonic Innovations, Inc. Subband acoustic feedback cancellation in hearing aids
EP1191813A1 (fr) * 2000-09-25 2002-03-27 TOPHOLM & WESTERMANN APS Prothèse auditive avec un filtre adaptatif pour la suppression de la réaction acoustique
EP2066139A3 (fr) * 2000-09-25 2010-06-23 Widex A/S Appareil d'aide auditive
US7092532B2 (en) 2003-03-31 2006-08-15 Unitron Hearing Ltd. Adaptive feedback canceller
US7756276B2 (en) 2003-08-20 2010-07-13 Phonak Ag Audio amplification apparatus
CN1926920A (zh) * 2004-03-03 2007-03-07 唯听助听器公司 包括自适应反馈抑制系统的助听器
ATE460053T1 (de) * 2004-12-16 2010-03-15 Widex As Hörgerät mit modellierter rückkopplungsverstärkungsschätzung
DE102005020317B4 (de) 2005-05-02 2009-04-02 Siemens Audiologische Technik Gmbh Automatische Verstärkungseinstellung bei einem Hörhilfegerät
DE102005028742B3 (de) * 2005-06-21 2006-09-21 Siemens Audiologische Technik Gmbh Hörhilfegerät mit Mitteln zur Rückkopplungskompensation und Verfahren zur Rückkopplungsunterdrückung
AU2005232314B2 (en) * 2005-11-11 2010-08-19 Phonak Ag Feedback compensation in a sound processing device
DK2002690T4 (da) * 2006-04-01 2020-01-20 Widex As Høreapparat, og fremgangsmåde til styring af adaptationshastighed i anti-tilbagekoblingssystemer til høreapparater
EP2003928B1 (fr) * 2007-06-12 2018-10-31 Oticon A/S Système anti-feedback en ligne pour appareil d'aide auditive
WO2008065209A2 (fr) * 2008-01-22 2008-06-05 Phonak Ag Procédé de détermination d'un gain maximal dans un dispositif auditif, et dispositif auditif
US8942398B2 (en) * 2010-04-13 2015-01-27 Starkey Laboratories, Inc. Methods and apparatus for early audio feedback cancellation for hearing assistance devices

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2008151970A1 *

Also Published As

Publication number Publication date
WO2008151970A8 (fr) 2009-02-26
EP2003928B1 (fr) 2018-10-31
EP3429232B1 (fr) 2023-01-11
US8923540B2 (en) 2014-12-30
US8503705B2 (en) 2013-08-06
US20140010395A1 (en) 2014-01-09
EP2533551B1 (fr) 2017-11-22
DK3429232T3 (en) 2023-03-06
DK2533551T3 (en) 2018-02-12
EP2160922B1 (fr) 2018-08-08
CN101836465A (zh) 2010-09-15
DK2003928T3 (en) 2019-01-28
DK2160922T3 (en) 2018-11-05
CN101836465B (zh) 2013-06-26
EP2533551A1 (fr) 2012-12-12
EP2003928A1 (fr) 2008-12-17
US20100232634A1 (en) 2010-09-16
WO2008151970A1 (fr) 2008-12-18
EP3429232A1 (fr) 2019-01-16

Similar Documents

Publication Publication Date Title
US8923540B2 (en) Online anti-feedback system for a hearing aid
US7650005B2 (en) Automatic gain adjustment for a hearing aid device
US11985482B2 (en) Neural network-driven feedback cancellation
EP3169085B1 (fr) Système d'assistance auditive avec détection de sa propre voix
EP3005731B1 (fr) Procédé de fonctionnement d'un dispositif auditif et dispositif auditif
US20100002896A1 (en) Hearing Aid Having an Occlusion Reduction Unit and Method for Occlusion Reduction
DK3021600T5 (en) PROCEDURE FOR ADAPTING A HEARING DEVICE TO A USER, A ADJUSTING SYSTEM FOR A HEARING DEVICE AND A HEARING DEVICE
EP2375787B1 (fr) Procédé et appareil pour une meilleure réduction du bruit pour dispositifs d'aide auditive
EP2339870B1 (fr) Système de surveillance d'événement de rétroaction acoustique pour dispositif d'aide auditive
US20100104123A1 (en) Method for adjusting a hearing device and corresponding hearing device
US9020171B2 (en) Method for control of adaptation of feedback suppression in a hearing aid, and a hearing aid
DK2595414T3 (en) Hearing device with a device for reducing a noise microphone and method for reducing noise of a microphone
EP3568995B1 (fr) Dispositif auditif avec commande de choc acoustique et procédé de commande de choc acoustique dans un dispositif auditif
US8385571B2 (en) Circuit for operating a hearing device and hearing device

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20100112

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL BA MK RS

17Q First examination report despatched

Effective date: 20100428

DAX Request for extension of the european patent (deleted)
GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: GRANT OF PATENT IS INTENDED

INTG Intention to grant announced

Effective date: 20180115

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

Ref country code: AT

Ref legal event code: REF

Ref document number: 1028447

Country of ref document: AT

Kind code of ref document: T

Effective date: 20180815

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 602008056387

Country of ref document: DE

REG Reference to a national code

Ref country code: DK

Ref legal event code: T3

Effective date: 20181022

REG Reference to a national code

Ref country code: NL

Ref legal event code: MP

Effective date: 20180808

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG4D

REG Reference to a national code

Ref country code: AT

Ref legal event code: MK05

Ref document number: 1028447

Country of ref document: AT

Kind code of ref document: T

Effective date: 20180808

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

Ref country code: LT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20181208

Ref country code: NL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

Ref country code: BG

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20181108

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20181109

Ref country code: NO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20181108

Ref country code: AT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

Ref country code: PL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

Ref country code: LV

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

Ref country code: HR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: EE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

Ref country code: CZ

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

Ref country code: RO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602008056387

Country of ref document: DE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20190509

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SI

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: MC

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

REG Reference to a national code

Ref country code: BE

Ref legal event code: MM

Effective date: 20190630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: TR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20190604

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LU

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20190604

Ref country code: BE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20190630

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: PT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20181208

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CY

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: HU

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO

Effective date: 20080604

Ref country code: MT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20180808

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: CH

Payment date: 20230702

Year of fee payment: 16

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20240604

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20240604

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DK

Payment date: 20240604

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20240604

Year of fee payment: 17